The present invention relates to a heat-developable photosensitive material. More specifically, the present invention relates to a heat-developable photosensitive material that is excellent in sensitivity and storage stability.
Reduction of waste solutions has been strongly desired in recent years in the field of films for medical diagnosis and photomechanical process from the viewpoint of environmental protection and space saving. Accordingly, techniques concerning heat-developable recording materials as the films for medical diagnosis and photomechanical process capable of performing exposure efficiently with a laser/image setter or a laser/imager and forming a clear black image exhibiting high resolution and sharpness have been required. Such a heat-developable recording material can offer to customers a simpler and environmentally benign heat development processing system in which chemicals in solution system is not necessary for processing.
There also arises the same requirement in the field of general image-forming materials, but particularly image for the medical diagnosis have characteristics in that a cold tone image is preferable because high image quality excellent in sharpness and graininess is necessary as precise imaging is required and, in addition, from the viewpoint of easiness of diagnosis. At present, various hard copy systems utilizing pigments and dyes such as ink jet printers and electrophotography prevail as general image-forming systems, but none of these systems are satisfactory as a medical image output system.
On the other hand, thermal image-forming systems making use of organic silver salts are described, e.g., in U.S. Pat. Nos. 3, 152,904 and 3,457,075, and D. Klosterboer, Thermally Processed Silver Systems, xe2x80x9cImaging Processes and Materialsxe2x80x9d, compiled by Sturge, V. Walworth, A. Shepp, 8th Ed., Chap. 9, p. 279, Neblette (1989).
A heat-developable photosensitive material generally has a photosensitive layer comprising a catalytically active amount of photocatalyst (e.g., a silver halide), a reducing agent, a reducible silver salt (e.g., an organic silver salt) and, if necessary, a toner which controls the tone of silver, which have been dispersed in a binder matrix. A heat-developable photosensitive material forms a black silver image by heating at high temperature (e.g., 80xc2x0 C. or more) after image exposure to cause an oxidation reduction reaction between a reducible silver salt (which functions as an oxidizing agent) and a reducing agent. The oxidation reduction reaction is accelerated by the catalytic action of the latent image of the silver halide generated by exposure. Therefore, the black silver image is formed in the exposed area.
These heat-developable image-recording materials are described in various literature including U.S. Pat. No. 2,910,377 and JP-B-43-4924 (the term xe2x80x9cJP-Bxe2x80x9d as used herein means an xe2x80x9cexamined Japanese patent publicationxe2x80x9d).
Various spectral sensitizing dyes have so far been used for silver halides for use in these heat-developable photosensitive materials and every endeavor has been made for attaining a higher sensitization and improving storage stability. For example, methods of using the sensitizing dyes disclosed in JP-A-2000-98525 and JP-A-2000-122206 (the term xe2x80x9cJP-Axe2x80x9d as used herein means an xe2x80x9cunexamined published Japanese patent applicationxe2x80x9d) are known. However, further improvement of storage stability has been required even when these sensitizing dyes are used.
An object of the present invention is to solve the above-described technical problems, i.e., an object of the present invention is to provide a heat-developable photosensitive material that has a high sensitivity and is an excellent in a storage stability.
As a result of eager investigation to solve the above problems, the present inventor has found that a heat-developable photosensitive material excellent in a sensitivity and storage stability can be obtained by using as a sensitizing dye a compound having specific structure in which two or more dyes are linked by covalent bonding, thus the present invention has been accomplished.
That is, the present invention comprises the following structure:
(1) A heat-developable photosensitive material comprising:
a support;
a photosensitive silver halide;
a non-photosensitive organic silver salt;
a reducing agent for a silver ion;
a binder; and
a compound represented by formula (A): 
wherein Da and Db each independently represents a dye chromophore; La represents a linking group or a single bond; qa and ra each represents an integer of from 1 to 100; qb represents an integer of from 1 to 4; Ma represents a counter ion for equilibrating the electric charge; and ma represents a number necessary to neutralize the electric charge of the molecule.
(2) The heat-developable photosensitive material as described in item (1), wherein the compound represented by formula (A) is a compound having a structure represented by formula (I): 
wherein D1 represents a dye chromophore; L1 represents a linking group or a single bond; q1 and r1 each represents an integer of from 1 to 100; q2 represents an integer of from 1 to 4; M1 represents a counter ion for equilibrating the electric charge; and m1 represents a number necessary to neutralize the electric charge of the molecule.
(3) The heat-developable photosensitive material as described in item (2), wherein D1 is a dye chromophore having a structure represented by one of formulae (XI), (XII) and (XIII): 
wherein L11, L12, L13, L14, L15, L16 and L17 each represents a methine group; p11 and p12 each represents 0 or 1; n11 represents 0, 1, 2, 3 or 4; Z11 and Z12 each represents an atomic group necessary to form a nitrogen-containing heterocyclic ring, and Z11 and Z12 each may be a condensed ring; M11 represents a counter ion for equilibrating the electric charge; m1 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; and R11 and R12 each represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group; 
wherein L18, L19, L20 and L21 each represents a methine group; p13 represents 0 or 1; q11 represents 0 or 1; n12 represents 0, 1, 2, 3 or 4; Z13 represents an atomic group necessary to form a nitrogen-containing heterocyclic ring; Z14 and Z14xe2x80x2 each represents an atomic group necessary to form a heterocyclic ring or an acyclic acidic terminal group together with (Nxe2x80x94R14) q11; Z13, and Z14 and Z14xe2x80x2 each may be a condensed ring; M12 represents a counter ion for equilibrating the electric charge; m12 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; and R13 and R14 each represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group; 
wherein L22, L23, L24, L25, L26, L27, L28, L29 and L30 each represents a methine group; p14 and p15 each represents 0 or 1; q12 represents 0 or 1; n13 and n14 each represents 0, 1, 2, 3 or 4; Z15 and Z17 each represents an atomic group necessary to form a nitrogen-containing heterocyclic ring; Z16 and Z16 each represents an atomic group necessary to form a heterocyclic ring together with (Nxe2x80x94R16)q12; Z15, Z16 and Z16xe2x80x2, and Z17 each may be a condensed ring; M13 represents a counter ion for equilibrating the electric charge; m13 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; and R15, R16 and R17 each represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group.
(4) The heat-developable photosensitive material as described in item (2), wherein the compound represented by formula (I) is a compound represented by one of formulae (XXI) and (XXII): 
wherein L11, L12, L13, L14, L15, L16, L17, p11, p12, n11, Z11 and Z12 each has the same meaning as in formula (XI); L2 represents a linking group; M14 represents a counter ion for equilibrating the electric charge; m14 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; and R21 represents an alkyl group, an aryl group or a heterocyclic group; 
wherein L18, L19, L20, L21, p13, q11, n12, Z13, Z14, Z14xe2x80x2 and R14 each has the same meaning as in formula (XII); L3 represents a linking group; M15 represents a counter ion for equilibrating the electric charge; and m15 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule.
(5) The heat-developable photosensitive material as described in item (2), wherein the compound represented by formula (I) is a compound represented by one of formulae (XXXIa), (XXXIb) and (XXXII): 
wherein Z51 and Z52 each represents an oxygen atom, a sulfur atom, a selenium atom, a nitrogen atom or a carbon atom; R51 represents an alkyl group, an aryl group or a heterocyclic group; L51, L52, L53, L54, L55, L56 and L57 each represents a methine group; V51, V52, V53, V54, V55, V56, V57 and V58 each represents a hydrogen atom or a substituent; L4 represents a linking group; M51 represents a counter ion for equilibrating the electric charge; and m51 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; 
wherein Z53 represents an oxygen atom, a sulfur atom, a selenium atom, a nitrogen atom or a carbon atom; R52 and R53 each represents an alkyl group, an aryl group or a heterocyclic group, provided that either two R52""s or two R53""s form L5 jointly; L5 represents a linking group; L58, L59, L60, L61 and L62 each represents a methine group; V59, V60, V61, V62, V63, V64, V65, V66, V67 and V68 each represents a hydrogen atom or a substituent; M52 represents a counter ion for equilibrating the electric charge; and m52 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule; 
wherein Z54 represents an oxygen atom, a sulfur atom, a selenium atom, a nitrogen atom or a carbon atom; Z55 represents an oxygen atom, a sulfur atom or a nitrogen atom; R54 represents an alkyl group, an aryl group or a heterocyclic group; L6 represents a linking group; L63, L64, L65 and L each represents a methine group; n51 represents 1 or 2; V69, V70, V71 and V72 each represents a hydrogen atom or a substituent; M53 represents a counter ion for equilibrating the electric charge; and m53 represents a number of 0 or higher necessary to neutralize the electric charge of the molecule.
(6) The heat-developable photosensitive material as described in item (1), wherein the compound represented by formula (A) is adsorbed in a single layer.
(7) The heat-developable photosensitive material as described in item (1), wherein the photosensitive silver halide has an average equivalent-circle diameter of from 10 to 50 nm.
(8) The heat-developable photosensitive material as described in item (1), which further comprises an image-forming layer containing the photosensitive silver halide, the non-photosensitive organic silver salt and the compound represented by formula (A).
(9) The heat-developable photosensitive material as described in item (8), wherein the image-forming layer further contains the reducing agent for a silver ion and the binder.
(10) The heat-developable photosensitive material as described in item (8), which further comprises a second image-forming layer containing the reducing agent for a silver ion and the binder.
The present invention is described in detail below. In the present invention, xe2x80x9cfrom x to yxe2x80x9d means the range including the numerical values x and y as the minimum value and maximum value respectively.
The compounds used in the present invention are described below. In the first place, the comprehensive definitions of the groups of the compounds for use in the present invention are described in detail.
When the specific moiety of a compound is called xe2x80x9ca groupxe2x80x9d in the present invention, the moiety itself may not be substituted, or may be substituted with one or more (with the possible maximum number of substituents) substituents. When the group can be substituted with a plurality of substituents, the substituents may be the same or different. For example, xe2x80x9can alkyl groupxe2x80x9d means a substituted or unsubstituted alkyl group. Any substituent which can be substituted for the groups of the compounds according to the present invention can be included in the substituents whether they are substituted or unsubstituted.
Taking these substituents as W, substituents W are not particularly restricted and any groups can be included, for example, a halogen atom, an alkyl group [(a cycloalkyl group, a bicycloalkyl group and a tricycloalkyl group are included), and an alkenyl group (a cycloalkenyl group and a bicycloalkenyl group are included) and an alkynyl group are also included], an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, a carboxyl group, an alkoxyl group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including an anilino group), an ammonio group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkylsulfonylamino group, an arylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfamoyl group, a sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an arylazo group, a heterocyclic azo group, an imido group, a phosphino group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a phospho group (also referred to as a phosphono group), a silyl group, a hydrazino group, a ureido group, a boronic acid group (xe2x80x94B(OH)2), a phosphato group (xe2x80x94OPO(OH)2), a sulfato group (xe2x80x94OSO3H), and other well-known substituents can be exemplified.
Further in detail, the examples of W include a halogen atom (e.g., fluorine, chlorine, bromine, iodine), an alkyl group {[a straight chain, branched, cyclic, substituted or unsubstituted alkyl group including an alkyl group (preferably an alkyl group having from 1 to 30 carbon atoms, e.g., methyl, ethyl, n-propyl, isopropyl, tert-butyl, n-octyl, eicosyl, 2-chloroethyl, 2-cyanoethyl, 2-ethylhexyl), a cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having from 3 to 30 carbon atoms, e.g., cyclohexyl, cyclopentyl, 4-n-dodecylcyclohexyl), a bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having from 5 to 30 carbon atoms, i.e., a monovalent group obtained by removing one hydrogen atom from a bicycloalkane group having from 5 to 30 carbon atoms, e.g., bicyclo[1,2,2]heptan-2-yl, bicyclo[2,2,2]octan-3-yl), and a tricyclohexyl structure having more ring structures; the alkyl group in the substituent described below (e.g., the alkyl group in an alkylthio group) represents the alkyl group of such a concept, in addition to the above, analkenyl group and an alkynyl group are also included], analkenyl group [a straight chain, branched, cyclic, substituted or unsubstituted alkenyl group including an alkenyl group (preferably a substituted or unsubstituted alkenyl group having from 2 to 30 carbon atoms, e.g., vinyl, allyl, prenyl, geranyl, oleyl), a cycloalkenyl group (preferably a substituted or unsubstituted cycloalkenyl group having from 3 to 30 carbon atoms, i.e., a monovalent group obtained by removing one hydrogen atom from a cycloalkene group having from 3 to 30 carbon atoms, e.g., 2-cyclopenten-1-yl, 2-cyclohexen-1-yl), a bicycloalkenyl group (a substituted or unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having from 5 to 30 carbon atoms, i.e., a monovalent group obtained by removing one hydrogen atom from a bicycloalkene group having one double bond, e.g., bicyclo[2,2,1]hepto-2-en-1-yl, bicyclo[2,2,2]octo-2-en-4-yl)], an alkynyl group (preferably a substituted or unsubstituted alkynyl group having from 2 to 30 carbon atoms, e.g., ethynyl, propargyl, trimethylsilylethynyl)}, an aryl group (preferably a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms, e.g., phenyl, p-tolyl, naphthyl, m-chlorophenyl, o-hexadecanoylaminophenyl), a heterocyclic group (preferably a 5- or 6-membered, substituted or unsubstituted, aromatic or non-aromatic monovalent group obtained by eliminating one hydrogen atom from a heterocyclic compound, more preferably a 5- or 6-membered aromatic heterocyclic group having from 3 to 30 carbon atoms, e.g., 2-furyl, 2-thienyl, 2-pyrimidinyl, 2-benzothiazolyl, further, a cationic heterocyclic group, e.g., 1-methyl-2-pyridinio and 1-methyl-2-quinolinio may also be included), a cyano group, a hydroxyl group, a nitro group, a carboxyl group, an alkoxyl group (preferably a substituted or unsubstituted alkoxyl group having from 1 to 30 carbon atoms, e.g., methoxy, ethoxy, isopropoxy, tert-butoxy, n-octyloxy, 2-methoxyethoxy), an aryloxy group (preferably a substituted or unsubstituted aryloxy group having from 6 to 30 carbon atoms, e.g., phenoxy, 2-methylphenoxy, 4-tert-butylphenoxy, 3-nitrophenoxy, 2-tetradecanoylaminophenoxy), a silyloxy group (preferably a silyloxy group having from 3 to 20 carbon atoms, e.g., trimethylsilyloxy, tert-butyldimethylsilyloxy), a heterocyclic oxy group (preferably a substituted or unsubstituted heterocyclic oxy group having from 2 to 30 carbon atoms, e.g., 1-phenyltetrazol-5-oxy, 2-tetrahydropyranyloxy), an acyloxy group (preferably a formyloxy group, a substituted or unsubstituted alkylcarbonyloxy group having from 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyloxy group having from 6 to 30 carbon atoms, e.g., formyloxy, acetyloxy, pivaloyloxy, stearoyloxy, benzoyloxy, p-methoxyphenylcarbonyloxy), a carbamoyloxy group (preferably a substituted or unsubstituted carbamoyloxy group having from 1 to 30 carbon atoms, e.g., N,N-dimethylcarbamoyloxy, N,N-diethylcarbamoyloxy, morpholinocarbonyloxy, N,N-di-n-octylaminocarbonyloxy, N-n-octylcarbamoyloxy), an alkoxycarbonyloxy group (preferably a substituted or unsubstituted alkoxycarbonyloxy group having from 2 to 30 carbon atoms, e.g., methoxycarbonyloxy, ethoxycarbonyloxy, tert-butoxycarbonyloxy, n-octylcarbonyloxy), an aryloxycarbonyloxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having from 7 to 30 carbon atoms, e.g., phenoxycarbonyloxy, p-methoxyphenoxycarbonyloxy, p-n-hexadecyloxy-phenoxycarbonyloxy), an amino group (preferably an amino group, a substituted or unsubstituted alkylamino group having from 1 to 30 carbon atoms, a substituted or unsubstituted anilino group having from 6 to 30 carbon atoms, e.g., amino, methylamino, dimethylamino, anilino, N-methylanilino, diphenylamino), an ammonio group (preferably an ammonio group, an ammonio group substituted with a substituted or unsubstituted alkyl group having from 1 to 30 carbon atoms, an aryl group or a heterocyclic group, e.g., trimethylammonio, triethylammonio, diphenylmethylammonio), an acylamino group (preferably a formylamino group, a substituted or unsubstituted alkylcarbonylamino group having from 1 to 30 carbon atoms, a substituted or unsubstituted arylcarbonylamino group having from 6 to 30 carbon atoms, e.g., formylamino, acetylamino, pivaloylamino, lauroylamino, benzoylamino, 3,4,5-tri-n-octyloxyphenylcarbonylamino), an amino-carbonylamino group (preferably a substituted or unsubstituted aminocarbonylamino group having from 1 to 30 carbon atoms, e.g., carbamoylamino, N,N-dimethylaminocarbonylamino, N,N-diethylaminocarbonylamino, morpholinocarbonylamino), an alkoxycarbonylamino group (preferably a substituted or unsubstituted alkoxycarbonylamino group having from 2 to 30 carbon atoms, e.g., methoxycarbonylamino, ethoxycarbonylamino, tert-butoxycarbonylamino, n-octadecyloxycarbonylamino, N-methylmethoxycarbonylamino), an aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonyl-amino group having from 7 to 30 carbon atoms, e.g., phenoxycarbonylamino, p-chlorophenoxycarbonylamino, m-(n-octyloxyphenoxycarbonylamino), a sulfamoylamino group (preferably a substituted or unsubstituted sulfamoyl amino group having from 0 to 30 carbon atoms, e.g., sulfamoylamino, N,N-dimethylaminosulfonylamino, N-n-octylaminosulfonylamino), an alkylsulfonylamino group and an arylsulfonylamino group (preferably a substituted or unsubstituted alkylsulfonylamino group having from 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfonylamino group having from 6 to 30 carbon atoms, e.g., methylsulfonylamino, butylsulfonylamino, phenylsulfonylamino, 2,3,5-trichlorophenylsulfonylamino, p-methylphenylsulfonylamino), a mercapto group, an alkylthio group (preferably a substituted or unsubstituted alkylthio group having from 1 to 30 carbon atoms, e.g., methylthio, ethylthio, n-hexadecylthio), an arylthio group (preferably a substituted or unsubstituted arylthio group having from 6 to 30 carbon atoms, e.g., phenylthio, p-chlorophenylthio, m-methoxyphenylthio), a heterocyclic thio group (preferably a substituted or unsubstituted heterocyclic thio group having from 2 to 30 carbon atoms, e.g., 2-benzothiazolylthio, 1-phenyltetrazol-5-ylthio), a sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having from 0 to 30 carbon atoms, e.g., N-ethylsulfamoyl, N-(3-dodecyloxypropyl)sulfamoyl, N,N-dimethylsulfamoyl, N-acetylsulfamoyl, N-benzoylsulfamoyl, N-(Nxe2x80x2-phenylcarbamoyl)sulfamoyl), a sulfo group, an alkylsulfinyl group and an arylsulfinyl group (preferably a substituted or unsubstituted alkylsulfinyl group having from 1 to 30 carbon atoms, a substituted or unsubstituted aryl sulfinyl group having from 6 to 30 carbon atoms, e.g., methylsulfinyl, ethylsulfinyl, phenylsulfinyl, p-methylphenylsulfinyl), an alkylsulfonyl group and an arylsulfonyl group (preferably a substituted or unsubstituted alkylsulfonyl group having from 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfonyl group having from 6 to 30 carbon atoms, e.g., methylsulfonyl, ethylsulfonyl, phenylsulfonyl, p-methylphenylsulfonyl), an acyl group (preferably a formyl group, a substituted or unsubstituted alkylcarbonyl group having from 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted hetero-cyclic carbonyl group having from 4 to 30 carbon atoms bonded to a carbonyl group via a carbon atom, e.g., acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, p-n-octyloxyphenylcarbonyl, 2-pyridylcarbonyl, 2-furylcarbonyl), an aryloxycarbonyl group (preferably a substituted or unsubstituted aryloxycarbonyl group having from 7 to 30 carbon atoms, e.g., phenoxycarbonyl, o-chlorophenoxycarbonyl, m-nitrophenoxycarbonyl, p-tert-butylphenoxycarbonyl), an alkoxycarbonyl group (preferably a substituted or unsubstituted alkoxycarbonyl group having from 2 to 30 carbon atoms, e.g., methoxycarbonyl, ethoxycarbonyl, tert-butoxycarbonyl, n-octadecyloxycarbonyl), a carbamoyl group (preferably a substituted or unsubstituted carbamoyl group having from 1 to 30 carbon atoms, e.g., carbamoyl, N-methylcarbamoyl, N,N-dimethylcarbamoyl, N,N-di-n-octylcarbamoyl, N-(methylsulfonyl)carbamoyl), an arylazo group and a heterocyclic azo group (preferably a substituted or unsubstituted arylazo group having from 6 to 30 carbon atoms, a substituted or unsubstituted heterocyclic azo group having from 3 to 30 carbon atoms, e.g., phenylazo, p-chlorophenylazo, 5-ethylthio-1,3,4-thiadiazol-2-ylazo), an imido group (preferably N-succinimido, N-phthalimido), a phosphino group (preferably a substituted or unsubstituted phosphino group having from 2 to 30 carbon atoms, e.g., dimethylphosphino, diphenylphosphino, methylphenoxyphosphino), a phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having from 2 to 30 carbon atoms, e.g., phosphinyl, dioctyloxyphosphinyl, diethoxyphosphinyl), a phosphinyloxy group (preferably a substituted or unsubstituted phosphinyloxy group having from 2 to 30 carbon atoms, e.g., diphenoxyphosphinyloxy, dioctyloxyphosphinyloxy), a phosphinylamino group (preferably a substituted or unsubstituted phosphinylamino group having from 2 to 30 carbon atoms, e.g., dimethoxyphosphinylamino, dimethylaminophosphinylamino), a phospho group, a silyl group (preferably a substituted or unsubstituted silyl group having from 3 to 30 carbon atoms, e.g., trimethylsilyl, tert-butyldimethylsilyl, phenyldimethylsilyl), a hydrazino group (preferably a substituted or unsubstituted hydrazino group having from 0 to 30 carbon atoms, e.g., trimethylhydrazino), and a ureido group (preferably a substituted or unsubstituted ureido group having from 0 to 30 carbon atoms, e.g., N,N-dimethylureido).
Two W""s may form a ring (an aromatic or non-aromatic hydrocarbon ring or heterocyclic ring) jointly.
These rings may further be combined to form a polycyclic condensed ring. Examples of such polycyclic condensed rings include a benzene ring, a naphthalene ring, an anthracene ring, a quinoline ring, a phenanthrene ring, a fluorene ring, a triphenylene ring, anaphthacene ring, abiphenyl ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, an indolizine ring, an indole ring, a benzofuran ring, a benzothiophene ring, an isobenzofuran ring, a quinolizine ring, a phthalazine ring, a naphthyridine ring, a quinoxaline ring, a quinoxazoline ring, an isoquinoline ring, a carbazole ring, a phenanthridine ring, an acridine ring, a phenanthroline ring, a thianthrene ring, a chromene ring, a xanthene ring, a phenoxthine ring, a phenothiazine ring, and a phenazine ring.
Of the above-described substituents W, those having hydrogen atoms may be substituted with the above groups after removing the hydrogen atoms therefrom. The examples of the substituents which are further substituted on substituents W include a xe2x80x94CONHSO2xe2x80x94 group (a sulfonylcarbamoyl group, a carbonylsulfamoyl group), a xe2x80x94CONHCOxe2x80x94 group (a carbonylcarbamoyl group), and xe2x80x94SO2NHSO2xe2x80x94 group (a sulfonylsulfamoyl group).
More specifically, an alkylcarbonylaminosulfonyl group (e.g., acetylaminosulfonyl), an arylcarbonylaminosulfonyl group (e.g., benzoylaminosulfonyl), an alkyl-sulfonylaminocarbonyl group (e.g., methylsulfonylamino-carbonyl), and an arylsulfonylaminocarbonyl group (e.g., p-methylphenylsulfonylaminocarbonyl) can be exemplified.
The compounds represented by formula (A) which are used in the present invention are described below.
In formula (A), Da and Db each represents a dye chromophore. Da and Db may be the same dye chromophore or may be different dye chromophores, preferably the same dye chromophore. Da and Db each preferably has the same meaning as D1 described later.
La represents a linking group or a single bond, and preferably has the same meaning as L1 described later.
qa and ra each represents an integer of from 1 to 100, preferably an integer of 1 to 5, more preferably an integer of 1 or 2, and particularly preferably 1.
When qa and ra each represents 2 or more, a plurality of La and Db contained may be linking groups, single bonds or dye chromophores different from each other.
qb represents an integer of from 1 to 4. qb being 2 or more means that each of Da and Db, and Db and Db are linked by a plurality of linking groups. That is, Da and Db, or Db and Db each may be linked at one point or at a plurality of points (from 2 to 4, preferably 2).
When qb represents 2 or more, a plurality of La are the same or different, preferably the same.
qb preferably represents 1 or 2, more preferably 1.
La may be linked with any moiety of Da and Db respectively, but preferably not the methine chain moiety. La is preferably bonded to Da and Db at the N-position of a basic nucleus or an acidic nucleus, more preferably at the N-position of a basic nucleus.
Ma represents a counter ion for equilibrating the electric charge. ma represents a number necessary to neutralize the electric charge of the molecule. Ma and ma each preferably has the same meaning as M1 and m1 described later.
Formula (A) represents that dye chromophores can be linked to each other in any way.
The dye chromophores, formulae and substituents of the more preferred ranges in the case where Da and Db are different in formula (A) are the same as those in the following description of formula (I) and the preferred ranges in the case where Da and Db are the same, except for the point that the dye chromophores are not the same.
That is, the dye chromophores of the more preferred ranges in the case where Da and Db are different in formula (A) are the dye chromophores represented by formula (XI), (XII) or (XIII) which are described in formula (I) and they are not the same.
When Da and Db are different in formula (A), more preferable dye chromophore is a compound represented by formula (XXI), wherein at least one of each two L11, L12, L13, L14, L15, L16, L17 p11, p12 n11, Z11, Z12 and R21 are not the same, or a compound represented by formula (XXII), wherein at least one of each two L18, L19, L20, L21, p13, q11, n12, Z13, Z14, Z14xe2x80x2 and R14 are not the same.
When Da and Db are different in formula (A), particularly preferable dye chromophore is a compound represented by formula (XXXIa), wherein at least one of each two Z51, Z52, R51, L51, L52, L53, L54, L55, L57, V51, V52, V53, V54, V55, V56, V57 and V58 are not the same, or a compound represented by formula (XXXIb), wherein at least one of each two Z53, R52, R53, L58, L59, L60, L61, L62, V59, V60, V61, V62, V63, V64, V65, V66, V67 and V68 are not the same, or a compound represented by formula (XXXII), wherein at least one of each two Z54, Z55, R54, L63, L64, L65, L66, n51, V69, V70, V71 and V72 are not the same.
Of the compounds represented by formula (A), a particularly preferred compound is a compound represented by formula (I). The compound represented by formula (I) corresponds to the compound represented by formula (A) wherein Da and Db each represents the same dye chromophore.
Formula (I) denotes that dye chromophores can be linked to each other in any way.
The compound represented by formula (I) is described below.
The compound represented by formula (I) has a plurality of same chromophores and is superior to the compound represented by formula (A) in storage stability (the case where Da and Db are different). Further, the compound represented by formula (I) is superior to the compound represented by formula (A) (the case where Da and Db are different) in the points that the compound represented by formula (I) can be synthesized more easily and manufactured inexpensively.
When the compound represented by formula (A) or (I) for use in the present invention is adsorbed in a single layer, the storage stability is high hence preferred.
xe2x80x9cAdsorbed in a single layerxe2x80x9d means that the dye chromophore of a compound (a sensitizing dye) is adsorbed onto the surface of a silver halide grain in one or less layer.
That is, the terms means that the adsorption amount of the dye chromophore per the unit surface area of a grain is in the state of not more than a monolayer saturation coating amount (a monolayer saturation coating amount means the adsorption amount of a dye per the unit surface area of a grain at the time of saturation coating of a single layer).
That is, the compound represented by formula (A) or (I) for use in the present invention is high in storage stability and preferred when the compound is not in the state of multilayer adsorption.
xe2x80x9cMultilayer adsorptionxe2x80x9d means that the dye chromophore of a compound (a sensitizing dye) is adsorbed onto the surface of a silver halide grain in more than one layer. That is, multilayer adsorption means that the adsorption amount of the dye chromophore per the unit surface area of a grain is in the state of more than a single layer saturation coating amount. An adsorption layer number is the adsorption amount with a single layer saturation coating amount as standard.
The detailed descriptions of the single-layer adsorption and the multilayer adsorption such as a measurement method are disclosed in JP-A-2000-267216, JP-A-2001-75222 and JP-2001-75226.
In the invention, the light absorption strength of a spectrally sensitized silver halide grain is preferably less than 100. When the wavelength of spectral absorption maximum is not more than 500 nm, the light absorption strength is preferably less than 60. When the light absorption strength is less than 100 or less than 60, the adsorption in a single layer is preferable in view of the high storage stability as described above. The light absorption strength is described in detail in JP-A-10-239789.
D1 and L1 are described below.
The dye chromophores represented by D1 are not restricted and any chromophores can be used, for example, a group comprising a cyanine dye, a styryl dye, a hemicyanine dye, a merocyanine dye, a trinuclear merocyanine dye, a tetranuclear merocyanine dye, a rhodacyanine dye, a complex cyanine dye, a complex merocyanine dye, a holopolar dye, an oxonol dye, a hemioxonol dye, a squarylium dye, a croconium dye, an azamethine dye, a coumarin dye, an arylidene dye, an anthraquinone dye, a triphenylmethane dye, an azo dye, an azomethine dye, a spiro compound, a metallocene dye, a fluorenone dye, a fulgide dye, a perylene dye, a phenazine dye, a phenothiazine dye, a quinone dye, an indigo dye, a diphenylmethane dye, a polyene dye, an acridine dye, an acridinone dye, a diphenylamine dye, a quinacridone dye, a quinophthalone dye, a phenoxazine dye, a phthaloperylene dye, a porphyrin dye, a chlorophyll dye, a phthalocyanine dye, or a metallic complex dye can be exemplified.
Preferably, polymethine chromophores, e.g., a cyanine dye, a styryl dye, a hemicyanine dye, a merocyanine dye, a trinuclear merocyanine dye, a tetranuclear merocyanine dye, a rhodacyanine dye, a complex cyanine dye, a complex merocyanine dye, a holopolar dye, an oxonol dye, a hemioxonol dye, a squarylium dye, a croconium dye, and an azamethine dye can be exemplified.
More preferably, a cyanine dye, a merocyanine dye, a trinuclear merocyanine dye, a tetranuclear merocyanine dye, an oxonol dye and a rhodacyanine dye can be exemplified, still more preferably, a group comprising a cyanine dye, a merocyanine dye or an oxonol dye, and most preferably a group comprising a cyanine dye or a merocyanine dye.
These dyes are described in detail in F. M. Harmer, Heterocyclic Compoundsxe2x80x94Cyanine Dyes and Related Compounds, John Wiley and Sons, New York, London (1964), D. M. Sturmer, Heterocyclic Compounds. Special Topics in Heterocyclic Chemistry, Chap. 18, Clause 14, pp. 482 to 515, John Wiley and Sons, New York, London (1977), and Rodd""s Chemistry of Carbon Compounds, 2nd Ed., Vol. IV, Part B, Chap. 15, pp. 369 to 422, Elsevier Science Publishing Company Inc., New York (1977).
As the preferred formulae of the dyes, the formulae on pages 32 to 36 in U.S. Pat. No. 5,994,051, and the formulae on pages 30 to 34 in U.S. Pat. No. 5,747,236 can be exemplified. Further, as the preferred cyanine, merocyanine and rhodacyanine dyes, those represented by formulae (XI), (XII) and (XIII) disclosed in columns 21 and 22 in U.S. Pat. No. 5,340,694 can be exemplified (however, the numbers of n12, n15, n17 and n18 are not restricted here and regarded as the integers of 0 or more (preferably 4 or less)).
D1 may or may not form J aggregates.
L1 is described below.
L1 represents a linking group (preferably a divalent linking group) or a single bond. L1 preferably represents a linking group. The linking group preferably comprises an atom or an atomic group containing at least one of a carbon atom, a nitrogen atom, a sulfur atom and an oxygen atom.
The linking group is preferably a linking group having from 0 to 100, preferably from 1 to 20, carbon atoms comprising one or more in combination of an alkylene group (e.g., methylene, ethylene, trimethylene, tetramethylene, pentamethylene), an arylene group (e.g., phenylene, naphthylene), an alkenylene group (e.g., ethenylene, propenylene), an alkynylene group (e.g., ethynylene, propynylene), an amido group, an ester group, a sulfoamido group, a sulfonic ester group, a ureido group, a sulfonyl group, a sulfinyl group, a thioether group, an ether group, a carbonyl group, xe2x80x94N(Va)-(wherein Va represents a hydrogen atom or a monovalent substituent, and the above-described W can be exemplified as the monovalent substituent), and a hetero-cyclic divalent group (e.g., a 6-chloro-1,3,5-triazine-2,4-diyl group, a pyrimidine-2,4-diyl group, a quinoxaline-2,3-diyl group).
The linking group may further have a substituent represented by W described above, or may contain a ring (e.g., an aromatic or non-aromatic hydrocarbon ring or a heterocyclic ring).
The linking group is more preferably a divalent linking group having from 1 to 30 carbon atoms, which comprises one or two or more in combination of an alkylene group having from 1 to 30 (e.g., methylene, ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, octamethylene, decamethylene), an arylene group having from 6 to 10 carbon atoms (e.g., phenylene, naphthylene), an alkenylene having from 2 to 30 carbon atoms (e.g., ethenylene, propenylene), an alkynylene having from 2 to 30 carbon atoms (e.g., ethynylene, propynylene), an ether group, an amido group, an ester group, a sulfoamido group, and a sulfonic ester group.
The linking groups may further be substituted with the above W.
It is more preferred that the linking group does not contain hetero atoms other than an amido group or an ester group, and it is still more preferred not to contain a hetero atom.
L1 particularly preferably represents the above alkylene group (e.g., ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, octamethylene, decamethylene, dodecamethylene), and the carbon atoms are preferably from 2 to 24, more preferably from 4 to 20, still more preferably from 6 to 18, far more preferably from 8 to 15, and particularly preferably from 12 to 14.
L1 is particularly preferably a linking group having a center of symmetry.
q1 and r1 each represents an integer of from 1 to 100, preferably an integer of from 1 to 5, still more preferably an integer of 1 or 2, and particularly preferably 1.
When r1 is 2 or higher, a plurality of L1 contained may be different linking groups or single bonds, but the same linking group or single bond is preferred.
When q1 or r1 is 2 or higher, a plurality of D1 bonded to L1 must be the same dye chromophore.
q2 represents an integer of from 1 to 4. q2 being 2 or high means that D1 and D1 are linked by a plurality of linking groups. That is, D1 and D1 may be linked at one point of each or at a plurality of points (from 2 to 4, preferably 2). When q2 represents 2 or higher, a plurality of L1 may be the same or different, preferably the same.
q2 preferably represents 1 or 2, more preferably 1.
L1 may be linked with any moiety of D1, but preferably not the methine chain moiety. L1 is preferably bonded to D1 at the N-position of a basic nucleus or an acidic nucleus, more preferably at the N-position of a basic nucleus.
D1 in formula (I) is preferably a methine dye represented by formula (XI), (XII) or (XIII), more preferably a methine dye represented by formula (XI) or (XII), and particularly preferably a methine dye represented by formula (XII).
Methine compounds represented by formula (I), (XI), (XII) or (XIII) are described in detail below.
In formula (XI), (XII) or (XIII), Z11, Z12, Z13, Z15 and Z17 each represents an atomic group necessary to form a nitrogen-containing heterocyclic ring, preferably a 5- or 6-membered nitrogen-containing heterocyclic ring, and a ring may be further condensed with these groups. The rings to be condensed with them may include an aromatic ring or a non-aromatic ring, preferably an aromatic ring, such as an aromatic hydrocarbon ring, e.g., a benzene ring and a naphthalene ring, and an aromatic heterocyclic ring, e.g., a pyrazine ring and a thiophene ring.
The examples of the nitrogen-containing heterocyclic rings formed by Z11, Z12, Z13, Z15 and Z17 include a thiazoline nucleus, a thiazole nucleus, a benzothiazole nucleus, an oxazoline nucleus, an oxazole nucleus, a benzoxazole nucleus, a selenazoline nucleus, a selenazole nucleus, a benzoselenazole nucleus, a tellurazoline nucleus, a tellurazole nucleus, a benzotellurazole nucleus, a 3,3-dialkylindolenine nucleus (e.g., 3,3-dimethylindolenine), an imidazoline nucleus, an imidazole nucleus, abenzimidazole nucleus, a 2-pyridine nucleus, a 4-pyridine nucleus, a 2-quinoline nucleus, a 4-quinoline nucleus, a 1-isoquinoline nucleus, a 3-isoquinoline nucleus, an imidazo[4,5-b]quinoxaline nucleus, an oxadiazole nucleus, a thiadiazole nucleus, a tetrazole nucleus, and a pyrimidine nucleus, preferably a benzothiazole nucleus, a benzoxazole nucleus, a 3,3-dialkylindolenine nucleus (e.g., 3,3-dimethylindolenine), a benzimidazole nucleus, a 2-pyridine nucleus, a 4-pyridine nucleus, a 2-quinoline nucleus, a 4-quinoline nucleus, a 1-isoquinoline nucleus, and a 3-isoquinoline nucleus, more preferably a benzothiazole nucleus, a benzoxazole nucleus, a 3,3-dialkylindolenine nucleus (e.g., 3,3-dimethylindolenine), and a benzimidazole nucleus, still more preferably a benzoxazole nucleus, a benzothiazole nucleus, and a benzimidazole nucleus, and most preferably a benzoxazole nucleus and a benzothiazole nucleus.
These nitrogen-containing heterocyclic rings may be substituted with substituents W or condensed with rings. The preferred substituents are an alkyl group, an aryl group, an alkoxyl group, a halogen atom, aromatic ring condensation, a sulfo group, a carboxyl group, and a hydroxyl group.
As the specific examples of the heterocyclic rings formed by Z11, Z12, Z13, Z15 and Z17, the similar rings to those exemplified as the examples formed by Z11, Z12, Z13, Z14 and Z16 disclosed in columns 23 and 24 in U.S. Pat. No. 5,340,694 can be exemplified.
The more preferred substituents W on Z11, Z12, Z13, Z15 and Z17 are a halogen atom, an aromatic ring and aromatic ring condensation.
Z14 and Z14xe2x80x2 each represents an atomic group necessary to form a heterocyclic ring or an acyclic acidic terminal group together with (Nxe2x80x94R14)q11. The heterocyclic ring (preferably a 5-or 6-membered heterocyclic ring) is not particularly limited but an acidic nucleus is preferred.
The acidic nucleus and the acyclic acidic terminal group are described below. Any forms of acidic nuclei and acyclic acidic terminal groups which are generally used in merocyanine dyes can be used in the present invention.
Preferably, Z14 represents a thiocarbonyl group, a carbonyl group, an ester group, an acyl group, a carbamoyl group, a cyano group or a sulfonyl group, more preferably a thiocarbonyl group or a carbonyl group. Z14xe2x80x2 represents the remaining atomic group necessary to form the acidic nucleus and the acyclic acidic terminal group. For forming an acyclic acidic terminal group, a thiocarbonyl group, a carbonyl group, an ester group, an acyl group, a carbamoyl group, a cyano group or a sulfonyl group is preferably used.
q11 represents 0 or 1, preferably 1.
Acidic nuclei and acyclic acidic terminal groups are described, for example, in James, The Theory of the Photographic Process, 4th Ed., pp. 198 to 200, Macmillan (1977). Acyclic acidic terminal groups here means acidic, i.e., electron-attractive terminal groups which do not form a ring.
Acidic nuclei and acyclic acidic terminal groups are specifically disclosed in U.S. Pat. Nos. 3,567,719, 3,575,869, 3,804,634, 3,837,862, 4,002,480, 4,925,777 and JP-A-3-167546, U.S. Pat. Nos. 5,994,051 and 5,747,236.
Acidic nuclei are preferably used to form a heterocyclic ring (preferably a 5- or 6-membered nitrogen-containing heterocyclic ring) comprising carbon, nitrogen and/or chalcogen atoms (typically, oxygen, sulfur, selenium and tellurium), more preferably to form a 5- or 6-membered nitrogen-containing heterocyclic ring comprising carbon, nitrogen and/or chalcogen atoms (typically, oxygen, sulfur, selenium and tellurium).
Specifically, the following nuclei are exemplified, e.g., 2-pyrazolin-5-one, pyrazolidine-3,5-dione, imidazolin-5-one, hydantoin, 2- or 4-thiohydantoin, 2-iminooxazolidin-4-one, 2-oxazolin-5-one, 2-thiooxazolidine-2,5-dione, 2-thiooxazoline-2,4-dione, isooxazolin-5-one, 2-thiazolin-4-one, thiazolidin-4-one, thiazolidine-2,4-dione, rhodanine, thiazolidine-2,4-dithione, isorhodanine, indane-1,3-dione, thiophen-3-one, thiophen-3-one-1,1-dioxide, indolin-2-one, indolin-3-one, 2-oxoindazolinium, 3-oxoindazolinium, 5,7-dioxo-6,7-dihydrothiazolo[3,2-a]pyrimidine, cyclohexane-1,3-dione, 3,4-dihydroisoquinolin-4-one, 1,3-dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, chroman-2,4-dione, indazolin-2-one, pyrido[1,2-a]pyrimidine-1,3-dione, pyrazolo-[1,5-b]quinazolone, pyrazolo[1,5-a]benzimidazole, pyrazolo-pyridone, 1,2,3,4-tetrahydroquinoline-2,4-dione, 3-oxo-2,3-dihydrobenzo[d]thiophene-1,1-dioxide, and 3-dicyanomethine-2,3-dihydrobenzo[d]thiophene-1,1-dioxide.
Further examples include nuclei having exo-methylene structure obtained by substituting a carbonyl group or a thiocarbonyl group constituting these nuclei on the active methylene position of acidic nuclei, nuclei having exo-methylene structure obtained by substituting a carbonyl group or a thiocarbonyl group on the active methylene position of active methylene compounds having the ketomethylene structure and cyanomethylene structure which are the raw materials of acyclic acidic terminal groups, and nuclei having these structures as a repeating unit. However, nuclei having the structure not substituting a carbonyl group or a thiocarbonyl group is preferred.
These acidic nuclei and acyclic acidic terminal groups may be substituted with substituents W or condensed with rings.
Of acidic nuclei and acyclic acidic terminal groups, acidic nuclei are preferred.
The preferred examples of the heterocyclic rings formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11 include hydantoin, 2-or 4-thiohydantoin, 2-oxazolin-5-one, 2-thiooxazoline-2,4-dione, thiazolidine-2,4-dione, rhodanine, thiazolidine-2,4-dithione, barbituric acid and 2-thiobarbituric acid, the more preferred examples are hydantoin, 2-or 4-thiohydantoin, 2-oxazolin-5-one, rhodanine, barbituric acid and 2-thiobarbituric acid, and the particularly preferred examples are 2- or 4-thiohydantoin, 2-oxazolin-5-one and rhodanine.
Rhodanine is most preferred.
As the heterocyclic rings formed by Z16, Z16xe2x80x2 and (Nxe2x80x94R16)q12, the same rings as described in the heterocyclic rings formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11 can be exemplified. The preferred heterocyclic rings are those obtained by eliminating an oxo group or a thioxo group from the acidic nuclei described in the explanation of the heterocyclic rings formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11.
The more preferred heterocyclic rings are those obtained by eliminating an oxo group or a thioxo group from the acidic nuclei exemplified as the specific examples of the heterocyclic groups formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11.
The still further preferred heterocyclic rings are the rings obtained by eliminating an oxo group or a thioxo group from hydantoin, 2- or 4-thiohydantoin, 2-oxazolin-5-one, 2-thiooxazoline-2,4-dione, thiazolidine-2,4-dione, rhodanine, thiazolidine-2,4-dithione, barbituric acid, or 2-thiobarbituric acid, the particularly preferred heterocyclic rings are those obtained by eliminating an oxo group or a thioxo group from hydantoin, 2-or 4-thiohydantoin, 2-oxazolin-5-one, rhodanine, barbituric acid, or 2-thiobarbituric acid, the particularly preferred heterocyclic rings are the rings obtained by eliminating an oxo group or a thioxo group from 2- or 4-thiohydantoin, 2-oxazolin-5-one, or rhodanine, and the most preferred heterocyclic rings are the rings obtained by eliminating a thioxo group from rhodanine.
q12 represents 0 or 1, preferably 1.
R11, R12, R13, R14, R15, R16 and R17 each represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group, preferably represents an alkyl group, an aryl group or a heterocyclic group.
The alkyl group, aryl group and heterocyclic group represented by R11, R12, R13, R14, R15, R16 and R17 include, e.g., an unsubstituted alkyl group having from 1 to 18, preferably from 1 to 7, and particularly preferably from 1 to 4, carbon atoms (e.g., methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, dodecyl, octadecyl), a substituted alkyl group having from 1 to 18, preferably from 1 to 7, and particularly preferably from 1 to 4 carbon atoms [e.g., an alkyl group substituted with the above-described substituents W] can be exemplified, in particular, alkyl groups having an acid radical described later are particularly preferred, preferably an aralkyl group (e.g., benzyl, 2-phenylethyl), an unsaturated hydrocarbon group (e.g., allyl and vinyl, i.e., an alkenyl group and an alkynyl group are to be included in the substituted alkyl group), a hydroxyalkyl group (e.g., 2-hydroxyethyl, 3-hydroxypropyl), a carboxyalkyl group (e.g., carboxymethyl, 2-carboxyethyl, 3-carboxypropyl, 4-carboxybutyl), an alkoxyalkyl group (e.g., 2-methoxyethyl, 2-(2-methoxyethoxy)ethyl), an aryloxyalkyl group (e.g., 2-phenoxyethyl, 2-(1-naphthoxy)ethyl), an alkoxycarbonylalkyl group (e.g., ethoxycarbonylmethyl, 2-benzyloxycarbonylethyl), an aryloxycarbonylalkyl group (e.g., 3-phenoxycarbonylpropyl), an acyloxyalkyl group (e.g., 2-acetyloxyethyl), an acylalkyl group (e.g., 2-acetylethyl), a carbamoylalkyl group (e.g., 2-morpholinocarbonylethyl), a sulfamoylalkyl group (e.g., N,N-dimethylsulfamoylmethyl), a sulfoalkyl group (e.g., 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2-(3-sulfopropoxy)ethyl, 2-hydroxy-3-sulfopropyl, 3-sulfopropoxyethoxyethyl), a sulfoalkenyl group, a sulfatoalkyl group (e.g., 2-sulfatoethyl, 3-sulfatopropyl, 4-sulfatobutyl), a heterocyclic group-substituted alkyl group (e.g., 2-(pyrrolidin-2-one-1-yl)ethyl, tetrahydrofurfuryl), an alkylsulfonylcarbamoylalkyl group (e.g., methanesulfonylcarbamoylmethyl), an acylcarbamoylalkyl group (e.g., acetylcarbamoylmethyl), an acylsulfamoylalkyl group (e.g., acetylsulfamoylmethyl), analkylsulfonylsulfamoylalkyl group (e.g., methanesulfonylsulfamoylmethyl)], an unsubstituted aryl group having from 6 to 20, preferably from 6 to 10, and more preferably from 6 to 8, carbon atoms (e.g., phenyl, 1-naphthyl), a substituted aryl group having from 6 to 20, preferably from 6 to 10, and more preferably from 6 to 8, carbon atoms (e.g., the aryl groups substituted with substituents W, specifically p-methoxyphenyl, p-methylphenyl, p-chlorophenyl can be exemplified), an unsubstituted heterocyclic group having from 1 to 20, preferably from 3 to 10, and more preferably from 4 to 8, carbon atoms(e.g., 2-furyl, 2-thienyl, 2-pyridyl, 3-pyrazolyl, 3-isooxazolyl, 3-isothiazolyl, 2-imidazolyl, 2-oxazolyl, 2-thiazolyl, 2-pyridazyl, 2-pyrimidyl, 3-pyrazyl, 2-(1,3,5-triazolyl), 3-(1,2,4-triazolyl), 5-tetrazolyl), and a substituted heterocyclic group having from 1 to 20, preferably from 3 to 10, and more preferably from 4 to 8, carbon atoms (e.g., the heterocyclic groups substituted with substituents W, specifically 5-methyl-2-thienyl, 4-methoxy-2-pyridyl).
As the groups represented by R11, R12, R13, R14, R15, R16 and R17, unsubstituted alkyl groups and substituted alkyl groups are preferred, and as the substituted alkyl groups, alkyl groups having an acid radical are preferred.
Acid radicals are described below. Acid radicals are groups having a dissociable proton.
Specifically, groups in which protons are dissociated by the pKa of the groups and the ambient pH can be exemplified, e.g., a sulfo group, a carboxyl group, a sulfato group, a xe2x80x94CONHSO2xe2x80x94 group (a sulfonylcarbamoyl group, a carbonyl-sulfamoyl group), a xe2x80x94CONHCOxe2x80x94 group (a carbonylcarbamoyl group), an xe2x80x94SO2NHSO2xe2x80x94 group (a sulfonylsulfamoyl group), a sulfonamido group, a phosphono group, a boronic acid group and a phenolic hydroxyl group. For example, proton-dissociating acid radicals in which 90% or more protons are dissociated at pH 5 to 12 are preferred.
More preferred examples are a sulfo group, a carboxyl group, a xe2x80x94CONHSO2xe2x80x94 group, a xe2x80x94CONHCOxe2x80x94 group, and an xe2x80x94SO2NHSO2xe2x80x94 group, and particularly preferably a sulfo group and a carboxyl group, and most preferably a sulfo group.
L11, L12, L13, L14, L15, L16, L17, L18, L19, L20, L21, L22, L23, L24, L25, L26, L27, L28, L29 and L30 each represents a methine group.
The methine groups represented by L11 to L30 may be substituted, and the above-described substituents W can be exemplified as the substituents.
For example, a substituted or unsubstituted alkyl group having from 1 to 15, preferably from 1 to 10, and particularly preferably from 1 to 5, carbon atoms (e.g., methyl, ethyl, 2-carboxyethyl), a substituted or unsubstituted aryl group having from 6 to 20, preferably from 6 to 15, and more preferably from 6 to 10, carbon atoms (e.g., phenyl, o-carboxyphenyl), a substituted or unsubstituted heterocyclic group having from 3 to 20, preferably from 4 to 15, and more preferably from 6 to 10, carbon atoms (e.g., N,N-dimethylbarbituric acid), a halogen atom (e.g., chlorine, bromine, iodine, fluorine), an alkoxyl group having from 1 to 15, preferably from 1 to 10, and more preferably from 1 to 5, carbon atoms (e.g., methoxy, ethoxy), an amino group having from 0 to 15, preferably from 2 to 10, and more preferably from 4 to 10, carbon atoms (e.g., methylamino, N,N-dimethylamino, N-methyl-N-phenylamino, N-methylpiperadino), an alkylthio group having from 1 to 15, preferably from 1 to 10, and more preferably from 1 to 5, carbon atoms (e.g., methylthio, ethylthio), and an arylthio group having from 6 to 20, preferably from 6 to 12, and more preferably from 6 to 10, carbon atoms (e.g., phenylthio, p-methylphenylthio) can be exemplified.
Each of these methine groups may form a ring together with other methine groups, or they may form a ring together with Z11 to Z17, or R11 to R17.
L11, L12, L16, L17, L18, L19, L22, L23, L29 and L30 each preferably represents an unsubstituted methine group.
n11, n12, n13 and n14 each represents 0, 1, 2, 3 or 4, preferably 0, 1, 2 or 3, more preferably 1, 2 or 3, and particularly preferably 2 or 3. n11 most preferably represents 3, and n12 most preferably represents 2. When n11, n12, n13 and n14 each represents 2 or more, the methine groups are repeated and these methine groups may be the same with or different from each other.
p11, p12, p13, p14 and p15 each represents 0 or 1, preferably 0.
Dye chromophore D1 may be linked with L1 at any position of the carbon atom moiety or the N-position of the basic nucleus of the dye chromophores, the N-position of the acidic nucleus, or the methine chain moiety, preferably the carbon atom moiety or the N-position of the basic nucleus, or the N-position of the acidic nucleus, more preferably the N-position of the basic nucleus or the N-position of the acidic nucleus (i.e., the case of linking through R11, R12, R13, R14, R15, R16 or R17 in formulae (XI), (XII) and (XIII)), and particularly preferably the N-position of the basic nucleus (i.e., the case of linking through R11, R12, R13, R15 or R17 in formulae (XI), (XII) and (XIII)).
M1, M11, M12 and M13 are included in the formulae to show the presence of a cation or an anion when a counter ion is necessary to neutralize the ionic charge of a dye.
Representative examples of cations include inorganic cations such as a hydrogen ion (H+), an alkali metal ion (e.g., a sodium ion, a potassium ion, a lithium ion), and an alkaline earth metal ion (e.g., a calcium ion), and organic ions such as an ammonium ion (e.g., an ammonium ion, a tetraalkylammonium ion, a triethylammonium ion, a pyridinium ion, an ethyl pyridinium ion, a 1,8-diazabicyclo[5,4,0]-7-undecenium ion).
Anions may be either inorganic anions or organic anions, and the examples include a halogen anion (e.g., a fluorine ion, a chlorine ion, an iodine ion), a substituted arylsulfonate ion (e.g., a p-toluenesulfonate ion, a p-chlorobenzenesulfonate ion), an aryldisulfonate ion (e.g., a 1,3-benzenedisulfonate ion, a 1,5-naphthalenedisulfonate ion, a 2,6-naphthalenedisulfonate ion), an alkylsulfate ion (e.g., a methylsulfate ion), a sulfate ion, a thiocyanate ion, a perchlorate ion, a tetrafluoroborate ion, a picrate ion, an acetate ion, and a trifluoromethanesulfonate ion. Further, CO2xe2x88x92 and SO3xe2x88x92 can be described as CO2H and SO3H respectively when they have hydrogen ions as the counter ions.
m1, m11, m12 and m13 each represents a number of 0 or higher necessary to neutralize the electric charge of the molecule, preferably from 0 to 4, and more preferably from 0 to 2. m1, m11, m12 and m13 each represents 0 when an inner salt is formed.
The compound represented by formula (I) is preferably selected from the compounds represented by formula (XXI) or (XXII).
In formulae (XXI) and (XXII), L11, L12, L13, L14, L15, L16, L17, p11, p12, n11, Z11, Z12, L18, L19, L20, L21, p13, q11, n12, Z13, Z14, Z14xe2x80x2 and R14 each has the same meaning as in formulae (XI) and (XII), and the preferred ranges are also the same.
Each of M14 and m14, and M15 and m15 has the same meaning as described in M1 and m1.
As R21, the same as the alkyl group, aryl group or heterocyclic group exclusive of a hydrogen atom among those described in R12 can be exemplified, and the preferred range is also the same.
As L2 and L3, the linking group exclusive of a single bond among those described in L1 can be exemplified, and the preferred range is also the same.
In formula (XXI), a particularly preferred combination is a case where n11 represents 2, and either the basic nucleus formed by Z11, L11, L12 and p11 or the basic nucleus formed by Z12, L16, L17 and p12 is a 4-quinoline nucleus, and the other is a benzoxazole nucleus or a benzothiazole nucleus (preferably a benzothiazole nucleus), or a case where n11 represents 3, and the basic nucleus formed by Z11, L11, L12 and p11 and the basic nucleus formed by Z12, L16, L17 and p12 are a benzoxazole nucleus or a benzothiazole nucleus (preferably at least one is a benzothiazole nucleus, and more preferably both are benzothiazole nuclei).
In formula (XXII),a particularly preferred combination is a case where n12 represents 2, and the basic nucleus formed by Z13, L18, L19 and p13 is a benzoxazole nucleus or a benzothiazole nucleus, and the acidic nucleus formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11 is a rhodanine nucleus, or a case where n12 represents 3, and the basic nucleus formed by Z13, L18, L19 and p13 is a benzothiazole nucleus, and the acidic nucleus formed by Z14, Z14xe2x80x2 and (Nxe2x80x94R14)q11 is a rhodanine nucleus.
Of formulae (XXI) and (XXII), formula (XXII) is preferred.
The compound represented by formula (I) is especially preferably selected from the compounds represented by formula (XXXIa), (XXXIb) or (XXXII).
In formulae (XXXIa), (XXXIb) and (XXXII), Z51, Z52, Z53 and Z54 each represents an oxygen atom, a sulfur atom, a selenium atom, a nitrogen atom (Nxe2x80x94V80), or a carbon atom (CV81V82).
V80, V81 and V82 each represents a hydrogen atom or a substituent (e.g., the above-described substituents W), preferably the same alkyl group, aryl group or heterocyclic group as represented by R11, and more preferably the same alkyl group. Z51 and Z52 each preferably represents an oxygen atom or a sulfur atom, more preferably at least either one represents a sulfur atom, and particularly preferably both represent sulfur atoms.
Z53 preferably represents an oxygen atom or a sulfur atom, and more preferably a sulfur atom. Z54 preferably represents an oxygen atom or a sulfur atom. When n51 is 1, Z54 more preferably represents an oxygen atom, and when n51 is 2, Z54 more preferably represents a sulfur atom. Z55 represents an oxygen atom, a sulfur atom or a nitrogen atom (Nxe2x80x94V83).
V83 represents a hydrogen atom or a substituent (e.g., the above-described substituents W), preferably the same alkyl group, aryl group or heterocyclic group as represented by R11, and more preferably the same alkyl group.
V51, V52, V53, V54, V55, V56, V57, V58, V59, V60, V61, V62, V63, V64, V65, V66, V67, V68, V69, V70, V71 and V72 each represents a hydrogen atom or a substituent (e.g., the above-described substituents W), and contiguous two substituents of these may be linked to each other to form a saturated or unsaturated condensed ring.
V51 to V72 each preferably represents a hydrogen atom, an alkyl group (e.g., methyl), an aryl group (e.g., phenyl), an aromatic heterocyclic group (e.g., 1-pyrrolyl, 2-thienyl), an alkoxyl group (e.g., methoxy), an alkylthio group (e.g., methylthio), a cyano group, an acyl group (e.g., acetyl), an alkoxycarbonyl group (e.g., methoxycarbonyl), or a halogen atom (e.g., fluorine, chlorine, bromine, iodine), or a case where contiguous two substituents are linked to each other to form an unsaturated condensed ring (e.g., a benzene ring) is preferred.
R51, R52, R53 and R54 each represents an alkyl group, an aryl group or a heterocyclic group, provided that either two R52""s form L5 jointly, or two R53""s form L5 jointly. As R51, R52, R53 and R54s, preferably the same groups as described above in R11 can be exemplified, and the preferred range is also the same.
R54 more preferably represents a carboxyalkyl group and most preferably a carboxymethyl group.
L51, L52, L53, L54, L55, L56, L57, L58, L59, L60, L61, L62, L63, L64, L65 and L66 each represents a methine group, and has the same meaning as L13, L14, L15, L20 and L21, and the preferred range is the same.
With respect to L51, L52, L53, L54, L55, L56 and L57, it is preferred that at least one of L52 and L54, L53 and L55, L54 and L56, and L52, L54 and L56 be linked to each other to form a ring. The ring is not limited, preferably a 5- or 6-membered hydrocarbon ring or a heterocyclic ring, and more preferably a 5- or 6-membered hydrocarbon ring.
Of the above, when three methine groups form a ring jointly, the ring is preferably a 5- or 6-membered hydrocarbon ring or a condensed ring of two heterocyclic rings, and more preferably a condensed ring of two 5- or 6-membered hydrocarbon rings.
These rings may be substituted with substituents W.
The specific examples of preferred ring structures are shown below. 
wherein Q represents CH2, O, S or Nxe2x80x94R100 (R100 is a hydrogen atom, or a monovalent substituent, e.g., substituents W)
In the above ring structures, substituents may be substituted at arbitrary positions (e.g., substituents W).
The examples of particularly preferred ring structures are shown below. 
wherein n represents 2 or 3.
Of L51, L52, L53, L54, L55, L56 and L57, methine groups not forming a ring are preferably unsubstituted methine groups.
With respect to L58, L59, L60, L61 and L62 each of L58, L59, L61 and L62 preferably represents an unsubstituted methine group, and L60 preferably represents an unsubstituted methine group or a methine group substituted with an alkyl group, and more preferably a methine group substituted with a methyl group.
With respect to L63, L64, L65 and L66, when n51 represents 1, L63, L64 and L66 each preferably represents an unsubstituted methine group, and L65 preferably represents an unsubstituted methine group or a methine group substituted with an alkyl group, and more preferably a methine group substituted with a methyl group.
When n51 represents 2, L64 and L65 are repeated but they need not be the same, preferably they are unsubstituted. A case where L64, L65 and L66 form at least one ring described in L51, L52, L53, L54, L55, L56 and L57 as a preferred case, and methine groups not forming a ring are unsubstituted methine groups is preferred.
n51 represents 1 or 2, preferably 1.
M51 and m51, M52 and m52, and M53 and m each has the same meaning as M1 and m1 above. L4, L5 and L6 each has the same meaning with the linking group exclusive of a single bond among those described in L1, and the preferred range is also the same.
Of formulae (XXXIa), (XXXIb) and (XXXII), formulae (XXXIa) and (XXXII) are preferred, and formula (XXXII) is more preferred.
The specific examples of the dye compounds represented by formulae (A) and (I) which are particularly preferably used in the present invention are shown below, but the present invention is not limited thereto.
In the first place, the specific examples of dye chromophores D1, Da and Db are shown (electric charge-equilibrating counter ions are omitted. These compounds may have any possible counter anion). 
In the next place, the specific examples of linking groups xe2x80x94L1xe2x80x94 or xe2x80x94Laxe2x80x94 are shown (electric charge-equilibrating counter ions are omitted. These compounds may have any possible counter anion).
Examples of linking groups xe2x80x94L1xe2x80x94 or xe2x80x94Laxe2x80x94
The specific examples of the compounds represented by formula (A) or (I) for use in the present invention are shown below.
The specific examples of D1xe2x80x94L1xe2x80x94D1 M1m1 (a case in which all of q1, q2 and r1 in formula (I) represent 1) are shown below.
Each of structural formulae DS-1 to DS-122 is linked with L1 at the position of the asterisk.
The specific example of a case wherein two D1""s are linked with two L1""s is shown below (a case in which q2 represents 2 and q1 and r1 represent 1 in formula (I)).
DS-44 is linked with L-55 at the position of the asterisk.
DD-69
The specific examples of a case wherein there are three or more D1""s are shown below (a case in which q2 represents 1, and either q1 or r1 represents 1 and the other represents 2 in formula (I)).
Each of structural formulae DS-1 to DS-122 is linked with L1 at the position of the asterisk.
DD-70
DD-71
The specific examples of Daxe2x80x94Laxe2x80x94Db Mama (a case in which all of qa, qb and ra in formula (A) represent 1) are shown below.
Each of structural formulae DS-1 to DS-122 is linked with La at the position of the asterisk.
The sensitizing dyes represented by formula (A) or (I) for use in the present invention can be synthesized according to the methods described in F. M. Harmer, Heterocyclic compoundsxe2x80x94Cyanine Dyes and Related Compounds, John Wiley and Sons, New York, London (1964), D. M. Sturmer, Heterocyclic Compounds Special Topics in Heterocyclic Chemistry, Chap. 18, Clause 14, pp. 482 to 515, John Wiley and Sons, New York, London (1977), and Rodd""s Chemistry of Carbon Compounds, 2nd Ed., Vol. IV, Part B, Chap. 15, pp. 369 to 422, Elsevier Science Publishing Company Inc., New York (1977).
The synthesis of the sensitizing dye represented by formula (A) or (I) for use in the present invention is described below by a specific example.